Caster



FIG. 1 is a first perspective view of a first embodiment of a caster showing our new design;

FIG. 2 is a second perspective view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a back view thereof;

FIG. 5 is a top view thereof;

FIG. 6 is a bottom view thereof;

FIG. 7 is a right view thereof;

FIG. 8 is a left view thereof;

FIG. 9 is an enlarged sectional view indicated in FIG. 3;

FIG. 10 is a first perspective view of a second embodiment of a caster showing our new design;

FIG. 11 is a second perspective view thereof;

FIG. 12 is a front view thereof;

FIG. 13 is a back view thereof;

FIG. 14 is a top view thereof;

FIG. 15 is a bottom view thereof;

FIG. 16 is a right view thereof;

FIG. 17 is a left view thereof; and,

FIG. 18 is an enlarged sectional view indicated in FIG. 12.

The broken lines shown in the figures show portions of the caster that form no part of the claimed design. 

CLAIM The ornamental design for a caster, as shown and described. 